Ratchet screw driver



Nov. 24l 1925. 1,562,862`

C. BODMER RATCHET SCREW DRIVER Filed Jan. 19. 1924 Patented Nov. 24, 1925.

I UNITED STATES PATENT OF FICE.

CHRISTIAN BODMER, OF NEW BRITAIN, CONNECTICUT, AVS-SIGNOR T THE STANLEY` WORKS, OF NEW BRITAIN,

CONNECTICUT, A CORPORATION .'OF CONNECTICUT.

RATCHET SCREW DRIVER.

Application led January 19, 1924. Serial No. 687,222.

T0 all "whom it may concern.'

Be it known that I, CH'Ris'riAN BODMER, a citizen of the United States, residing at New Britain, county of Hartford, and State of Connecticut, have invented certain new\ and useful Improvements in -Ratchet Screw Drivers, fully described and represented in the following specification and the accompanying drawings, forming a part of the same.

This invention relates to ratchet screw drivers and like tools.

It is the principal object of the invention to provide an improved ratchet screw driver or similar tool that is strong and durable and that is economical to manufacture.

I/Vith this general object in View the invention consists in the features, combinations, details of construction and arrangements of parts which will irst be described in connection with the accompanying draw ing and then more particularly pointed out.

Fig. l is a face view of a screw driver conf structed in accordance with the invention, parts being shown broken away and in section;

Fig. 2 is an enlarged view showing part of the screw driver in longitudinal section;

Fig. 3 is a similar' view, the section being taken at right angles to that of Fig. 2;

Fig. .ais a` sectional view taken on the line 4-4 of Figs. 2 and 3;

Fig. 5 is a similar view showing a ditl'er-v ent position of the parts;

Figs. 68 are sectional views taken on lines 6 6 to 8 8 of Figs. 2.and 3;

Fig. 9 vis a perspective view of the pawl carrier removed;

Fig. 10 is a perspective view of the paw housing removed;

Fig. 11 is a similar view of the pawl spring removed;

Fig. 12 is a plan and,

Fig. 13 is an enlarged view of part of Fig. 8.

Referring to the drawing, in which the invention is illustrated as embodied 1n a. ratchet screw driver, there is provided a blade, or part to be operated, having a rachet thereon. In the embodimentillustrated, a blade is formed from round stock and is suitably shaped at its outer end, as'indicated at 21r (Fig. Adjacent, but short view of one-of the pawls;

' structures embodying the invention 'to what of, the inner end of the blade is pinned or otherwise secured, a ratchet 22. This ratchet has alternate teeth 23 and grooves 24 paralleling the axis of the blade, the ratchet having a form somewhat like a spur gear (Figs. 3 and 8).

Cooperating with the ratchet are two reversely acting'selective pawls,either oneof' which may be thrown out of action, and in is now considered the best advantage, the pawls are freely positioned in open grooves in a carrier, the grooves being located side by 'side in a plane. Although capable of vai rions constructions in that here shown as an example, a carrier 25 is formed from a cylindrical block and is provided with two open parallel grooves 28, 28a, located side by side, and having flat bottoms lying in the 'same plane. These grooves, as shown, are separated by a. dividing wall 29 and are bounded by side abutment walls 30, 30, which are substantially perpendicular to the groove bottoms. These grooves may be formed by suitable cutters as hereinafter described. Forward of the grooves the block forming the carrier is hollowed out to provide a recess 26 for receiving the ratchet.. This recess is enclosed by a sleeve like part of the block which'houses the ratchet 22 with a close guiding fit, the recess having substan tially the same length as the ratchet.` The sleeve like part of the block is cut away (Fig. 9) adjacentthe grooves 28, 28, to give access to the ratchet for the pawls, As

shown, the walls defining the cut away p0rtijon are continuations of the walls` 30, 30a. The block forming the carrier, in the present embodiment, is bored, as at 27, at 'the inner end of the ratchet receiving recess, to provide a bearing for the inner4 end of the blade 2 0, the face of the block surrounding this bore 27 serving as anabutment for the inner face of the ratchet, as later referred to.

` Freely positioned inthe grooves 28, 28a, are the pawls 32, 32a. These pawls, as here exemplified,l comprise long flat bars v"of a width to fit within the grooves and of a length to project forwardly asubstantial 105 distancev over the ratchet. `Normally pawls are seated on the groove bottoms. ln this .position theforward ends of thepawls lie in a plane thatcuts the circumference of.

'the ratchet (Fig. s), the pawl' 32 being 11e nl l 1,509,302

located between a ratchet tooth and ythe side wall 30 and the pawl 328L being .located between the opposite. side of the same ratchet tooth and the side wall 30. In this connection, it is noted that the awls are wider than the ratchet grooves -an so cannot drop into the latter, thereby jamming the'ratchet mechanism. As illustrated in Fig.'v 8, when the pawl is forced a ainst the ratchet the bite of the pawl is su tantially at the root ofthe ratchet tooth. f

To enable either pawl to be thrown out of action, rovision 1s made for permitting tilting o the pawls into an inactive position. To this end, as here shown as an example, the grooves 28, 28* and their walls terminate, at the inner end, at a flat surface 35 the plane of which is stepped'down' from the plane of the pawl grooves (Fig. 3). The

`rear ends of the pawls are suspended over the surface 35 and can be tilted over the ledge formed'between this surface and the groove bottoms.

The pawls of the` resent, embodiment are constructed to enab e them to be anchored against forward movement and so as to be interchangeable duplicates. T10 this end, the pawls are roughly T-shaped, the widened ends 34, 34* being suspended over the surface' 35as above described. When the, pawl 32 is in position, the shoulders formedby tli'c widened portion 34. are hooked around the ends of the. side wall 3() and the dividing wall 29.- Similarly the shoulders of pawl 32l are hooked around the ends of the side wall 30 and the wall 29. This relation ofY the parts aids in locating the pawls' during assembly and anchors them against any forward'dislodgment.

The pawls are conveniently formed by a simplestamping operation and as they are interchangeable duplicates only-one set of.

stamping`tools isrequired. Moreover, `the pawls are interchangeable without reversal of the direction of facing because of the T- -shape with symmetrical shoulders.' In

punching articles from sheet'metal, the face the -0111er' face has sharp edges.

of the stamping opposed to the female die ordinarily, has slightly rounded vedges while spring element common to thetwo wls and on top -o the atter. Although. capable of various conhere shown as an example, the

It is cone' ratchet spring element is rouglil U-shaped Aand comprises a cross bar 37 an two bent sprring arms 38, 38* (Fig. 11). The spring is eely psitioned on the pawls with vthe cross-bar 38 seated on both pawlsand the forward end of each arm seated on its corresponding pawl (Figs. 2 and 3). In the present embodiment, the dividing wall 29 is formed with a notch 39 which receives the cross bar 37 of the spring. This `notch aids in locating the spring and -anchors it against lon itudinal movement. The spring element/ escribed may conveniently be formed a simple stamping o ration.

There is provi ed an abutment for the convex spring arms 38, 38%` This may be conveniently accomplished bymeans of an clement which serves as a retaining housing for the springand pawls and provides a bearing for the blade and an anchoring abutment for the ratchet. Although capable of variousconstructions, in the present embodiment, embracin the pawl carrier 25 with slip fit is a cy indrical housing 43 of 'a -length to house the carrier. The parts are so arranged that the inner wall of the housing serves as an abutment for the spring arms 38,38a and the housing serves as a retaining housing for the freely 'positioned 55 pawls and sprin element.- At its forward end the housing has a solid,contracted por# tion 44, bored to provide a bearing for the blade outside the ratchet.. The inner face of this ortion 44 provides an abutment for the orward face lof lthe ratchet..v The housing may be secured to the carrier in any suitable manner such, for example, as a cross pin 45 which passes throughfa' hole bored in the body'of 'the carrier and alining holes in the housing.

-With the construction described, not only does the element 43 serve as a housing and as an abutment for the bent bar spring element, but its' solid portion 4 in connection Awith the end of the solid portion of the carrier confines the ratchet and thus firmly an chors the blade against .longitudinal play.

ilo.

Moreover, thehousing and carrier together provide bearings for the blade on'both sides construction.

There is provided selective means for placing one pawl or the other into an iiiactive Although capable of variof the-ratchet, thus giving a strong, rugged ous constructions, as here shown as an verrample, rotatably mounted on the housing 43, at its rear or inner end, is a knurled col'- iis lar 5 0. Extending radially inwardly' from the collar 50 is a pin or lug 51 locatedover the rear ends'of the plawls, the housing `having a cut-away -notc 52 to provide access to the pawls. The lug 51 is. of such length that w enit is located between thepawls (Figs. 2`4;)1 it is clear of both' of them.

however, thesleeve ia` rotated slightly to the right of this neutral position, the lug presses down the rear end of one pawl and thus tilts the forward end upwardly away from the ratchet, the pawl tilting over the ledge formed by the junction of the groove and the stepped surface 35. By turning the collar to the other side of the neutral position,`its lug 51 similarly tilts the other pawl into an inactive position. y

There is provided means for. releasably holding the selective means inflshifted Iposition. This may be accomplished, for example, by a friction spring,- and in structures embodying the invention to the best' advantage, the spring is of a type easy to assemble. As here shown as an example, a bent bar spring 54 is located between the collar and the housing 43. This spring seats in a shallow circumferential ygroove 55 formed on the interior of the collar 50. Then the parts are assembled the spring is bent into substantially the are of the collar and by its pressure between collar andl housing, it releasably holds the collar in shifted position. To assemble the parts the spring is placed in the groove and vbent to its arc, by pliers or any suitable tool, `until the sleeve is slipped over the housing. The

ends of the notch 52 act, if necessary, as

stop means for the movements of the lug 5l.l The collar and housing may be given any suitablel markings to indicate neutral position. In the embodiment here illustrated the collar 50 extends forwardly beyond pin 45 and so serves to retain the latter in position.-

A 'handle is provided and in structures embodying the invention to the best advantage the handle servesvas an end retaining wall for the pawl carri-er and its associated parts. As here illustrated as an example, integral with the carrier block 25 is a rearwardly extending stem 57. Secured to this stem by means of a pin 58 is a solid wooden handle 59 having a flat end face bored to receive the stem.y As sho-wn in Figs. 2 and '3, the pawl carrier 25, the housing 43 and the collar 50 are substantially c-onterminous. When the handle is in place, its flat end face is in close proximity to the parts just mentioncd and serves as an end retaining or stop wall. lin the present embodiment, a nietal washer (30 is located between the end `of the handle and the pawl carrier and associated parts. T his washer serves, ineffect, as a metal facing for the end of the'wooden handle.

The pawl carrier above described makes possible a desirable type of pawl and ratchet nechanisin and at the same time it is relatively economical to manufacture. The carrier illustrated may conveniently be made asl follows: From rod stock a cylindrical block and stem of the desired dimensions are formed. By means ot screw machine operaflat surface35 the Second ents not-ch 39 for anchoring the spring element; the third cuts 0H" the div'ding wall 29 at the endfof the grooves and thus completes the formation of. the cut awa-y portion of the Vblock at the recess 26. These cross cutting ol'gierations form notches in the side walls 30, 30, as appears in Fig. 9 but these notches do no-t interfere with the function of the walls. During these milling operations the blocks are conveniently located in the jigs by means of the transverse pin hole. Sets of cutters in a gang for milling several blocks simultaneously may, of course, be used.

In operation, assuming the selective collar 50 to be shifted to the right (looking from the handle down the blade), the lug 5l engages the rfght hand pawl 32 and tilts the same into an inactive position. driver is now arranged for right hand, i. e., clockwise, operation.. As the handle and carrier 25, which are secured together to move as a unit, are turned to the right, the ratchet is moved with them. This results in a like rotation of the operated part, e. g., the blade 20, for driving. a screw due to the pawl 32a being forced by the carrier against a ratchet tooth. Following each drivingr stroke the handle may be ygiven an idle reverse rot-ation. During such idle stroke the blade remains stationary as the carriermoves The screw around the' ratchet, the pawl sliding over the ratchet teeth. IAt the end of therevcrse stroke of the handle the pa'wl drops into po'- sition behind another ratchet tooth because of spring arm 38i1 and the driving stroke mayI be repeated.

For a' left hand. or counter clockwise drive,

the collar 50 is shifted over to the left. This.

releases pawl 32, which is moved back to 1 active'postion by its spring arm 38. and lug v51 tilts the other pawl 32f1 into inactive posi-` between the two pawls, 'engaging neither, and both pawls are in active or locked position. Consequently, in whichever direction the handle is turned, handle and blade turn as a unit.

With the construction described the parts are easily and economically assembled; the

'construction is such that any applied force is transmitted to the blade, short of a force suicent to crush the pawls; and the tool as a whole is strong and durable and is economical to manufacture;

What I claim is: Y

1. A pawl carrier for a ratchet screw driver or like tool comprising a block having a ratchet receiving recess, two pawl-receiving' open. parallel grooves located side b y side in a, plane, a flat surface at which the dividing wall and outer walls of the grooves terminate andfwhich lies in .a plane lower than that of the grooves, the wall of the ratchet-receiving recess' being cut 'away adjacent the grooves, with the walls defining the cut away portionbeing continuations of 1 'the outer walls of the grooves.

2. A pawl carrier for a ratchet lscrew driver or'like tool comprising a block having a ratchet-receiving recess, 4two pawl-receive ing open parallel' grooves located side by side in a. plane, a surface at which'the dividing I wall and outer walls of the grooves terminate vversely acting and which lies in a plane lower than'that of the grooves, the dividing wall between the grooves having a cross notch for receiving 'a spring element, and the block having a.

transverse hole for receiving a pin.

3. A screw driver or like tool comprisi 'a cylindrical block having a recess for a r'atc et ,and two grooves for pawls, the portion of the block dening said recess being cut away to vform abutment walls in continuation of the outer walls of said grooves, a blade having -a ratchet .thereon with its teeth and grooves paralleling the axis of the blade, the

ratchet being located in said recess, two resaid grooves an having their ends extending over said ratchet, a spring element freely vmounted on said pawls, the block being cut away to the rear of said grooves to rovide a'ledge overwhich, the pawls may ti t', a cylindrical housing closely fitting sa'id' block and providing an abutment for said spring element and having a ratchet-anchoring portion at its forward end, and selective means for engaging one pawl or the other to t1lt the same into inactlve position with relation 'tothe ratchet.

4. A screw driver or liketool comprising -V for receiving a handle an at one end a stem at the other end a ratchet-receiving recess and havlng Atwo a cylindrical block having grooves forv pawls, the portion of the block' deining'said recess being cut away to form abutment walls in continuation of the outer' (pawls freely positioned in.

a ledge over which the pawls may tilt, a cy- 7 lndrlcal housing closely itting said block ,and providing an abutment for said spring clement and having a ratchet-anchoring portion at its forward end, a collar rotatably',

mounted onthe housing, a pawl engaging 30 .element on said collar for engaging one pawl or the other to tilt the same into inactive po' sition with respect to the ratchet, the housing belng cut away to give said element access tothe rear ends of the pawls, and a handle on said stem.

5. A screw driver or like tool comprising a cylindrical block having a recess for a ratchet and being cut away to form seats and op ositely disposedabutment walls for 9 pawls, the portion of the block definingsaid recess beine` cut' away to form continuations of said abutment walls, a/blade having a ratchet thereon located in said recess, two reversely acting pawls freely positioned on 95 said seats and'between said walls and havmg their ends extending over said ratchet, a

spring element freely mounted on said pawls, f

the block being formed to permit tilting of thepawls, a vcylindrical housing closely'it- 1 ting said blockjand providing an abutment for said spring element, andselective means 'for "tilting one pawl or the other into inac#- tive position with respect to the ratchet.

6: A screw driver or like tool comprising 105- a blade havingy a ratchet thereon, acylindrical block formed with a ratchet-receiving recess ;and two pawl-receiving openparallel grooves located side by side in a plane, thel lock having a surface at which the dividing no wall and outer walls of the grooves terminate and whichv lies .in a plane lower than that of the grooves and havingr a cross notch, two reversely acting pawls 1 located in said; grooves and having their ends extending vover ratchet, and. over lsaid surface, a :spring element comprlsing two leaf sprin and a cross b ar freely. mounted on said paw s 'with its cross b ar located in said notch, a cylindricalhousingenclosing said block and 12* serving-as an abutment for the springs, and selective means for' tilting one awl or the other -over the shoulder formed ltween the grooves and said surface. ,I k

7. A screlvl driver -or like tool comprising l a blade ha ng a ratchet thereon short of the end thereof, .a cylindrical block formed with a recess for receiving said ratchet and having an axial bore or recess* for receiving the inner end of the blade,"saidfblock having 1 grooves for pawls, the

Aing S19 portion of theblock defining said ratchet-receiving recess being cutaway, to form abutment walls in continuation of the outer wallsof said grooves, tworeversely acting pawls freely seated in said grooves and, having their ends extending over said ratchet, a spring element freely mounted on said awls, the block being formed .to permit ti ting of the p awls, a cylindrical housing closely -tting said block and serving'as an abutment' for/said spring` element and having a ratchet-anchoring portion, and selective means for tilting one pawl or-the other into inactive position.

8. AY pawl carrier for a ratchet screw driver or like tool comprising a block having 4a ratchretreceivn Y in a plane,-a surface at whichj the divi recess, two pawl-receiv' open paralle grooves located side b ing wall and outer'walls of the grooves termlnat'eand which lies in a plane lower than that of the grooves, the dividing wall betwen the grooves having across notch for receiving a spring element.

9. A pawl carrier for a ratchet screw driver or like tool comprising a block having a ratohetireceiving recess, formed with flat axial'surfaces, for receivingl pawls, and opposing abutment walls, the portion of the block defining the recess-being cut away to form continuations of said walls, and the block Abeing cut down attire end of said surfaces to form shoulders therewith over which Rawls may be tilted.

I n testimony w my hand.

oHnis'rIAN BODMER.

the block being.

ereof, I have hereunto set 35 

